Electrical connector



March 21, 1939. o F, TALLMAN 2,150,994

ELECTRICAL CONNECTOR Filed May 10, 1957 Mum/701a 0504/? E DIAL/WAN A IrO/E/YEY Patented 21, 1939 UNITED STATES 2,150,994 nmc'rarcnr. comc'ron Oscar F. Tallman, St. Louis, MO., assignor to James B. Kearney Corporation, St. Louis, Mo., a corporation of Missouri Application May 1o,1aa':,sene1 No. 141,509 Claims. 01. 24-125) This invention relates generally to electrical connectors and more specifically to wire connectors of the split bolt type which are used extensively in the construction, repair, and maintenance of electric wire systems for connecting tap or service lines or ground wires to main lines, and for numerous other purposes, such, for instance, as connecting wires to articles of electrical equipment, the predominant object of the invention being to provide a connector of the type mentioned which is of such improved construction and arrangement that the function of the connector is performed in an improved and highly efllcient manner.

Connectors of the type towhich this invention relates comprise a bolt in which a slot is formed longitudinally thereof, said slot being open at one end of the bolt and terminating at itsbpposite end in a wire seat which receives a wire to be clamped. Theopposed legs of the slotted bolt are exteriorly screwthreaded throughout most.

of their lengths and screwthreadedly mounted on the screwthreaded portions or the legs of the bolt is a. nht which has associated therewith a washer, said washer being movable longitudinally of the bolt of the connector with the nut but being restrained from rotary movement with said nut by a portion of the washer which extends into the slot of the bolt.- The washer ordinarily a0 is provided with a wire seat which is movable into and out of wire clamping relation with respect to the wire seat of the bolt by manipulation of the nut.

A source of considerable annoyance in the use of connectors of the type described is that it is not always possible to obtain connectors having screwthreads on, the bolts and within the nuts thereof which are formed with such precision as to provide the desired intimate contact and perfect cooperation between the screwthreads of the nuts and bolts. The main purpose of this invention, therefore, is to provide an improved connector having a washer of such unique construction and arrangement that when pressure is applied to elements being clamped between the seats of the bolt and the washer, such pressure will spread opposed portions of the washer in such manner as to force the legs of the bolt outwardly away from each other. This results in the screwthreads on the legs of the bolt being forced into intimate contact with the screwthreads of the nut to provide the desired close cooperation between. the screwthreads of the bolt and the nut of the connector.

Another object of the invention is to provide a connector of the type to which this invention relates which is provided with a washer formed by bending into proper shape one or more elongated strips of material such as relatively heavy wire or the like. BY pr viding the improved con- 5 nector with a washer of the type mentioned the connector and the manufacture thereof are simplified without in any manner impairing the efllciency of the connector.

Fig. 1 is a side elevation of the improved con- 10 hector.

Fig. 2 is a vertical section through the connector illustrated in Fig. 1.

Fig. 3 is a section taken on line 3-4 of Fig. 1.

Fig. 4 is a horlzontaisection taken on line 4-4 16 of Fig. 1.

Fig. 51s a perspective of a-modifled form of the I washer of the improved connector.

In the drawing, wherein are shown for purposes of illustration, merely, two embodiments of the go invention, A designates, in Figs. 1, 2, 3, and 4, the improved connector generally. The connect'or A includes a bolt l which is provided at one of its ends with a head 2 preferably, though not necessarily, of noncircular shape so that a tool 35 may be applied thereto if desired. The bolt I has formed longitudinally thereof a slot 3 which is open at an end of the bolt and at its opposite end terminates in a wire seat 4 which is located at the lower portion of the head 2. The presence of 30 the slot 3 in the bolt i of the connector provides said bolt with opposed legs I which throughout at least a portion of their lengths are externally screwthreaded as indicated at 5.

Mounted on the screwthreaded portions of the 35 bolt 1 is a. nut 6 and associated with said nut in assembled ,relation therewith is a washer I. The washer 1 shown in Figs. 1, 2, 3, and 4 is in the form of two, independent washer portions la. and lb and each washer portion includes an arcuate 4o portion l which is arranged in embracing relation with respect to the curved outer face of the adJacent leg I of the bolt as shown to the best advantage in Fig. 4. The lower faces of the arcuate portions 8 of the washer portions Ia and 5 lb contact with the top face 6' of the nut as these parts are positioned in Figs. 1 to 4 inclusive, and each washer portion la and 1b includes portions 9 which extend inwardly toward each other from the opposite ends of the arcuate portion 8 of said .0 washer portion as shown in Fig. 4. From the inner ends of the inwardly extended portions 9 of each washer portion Ia and lb portions ill of the washer portion extend downwardly through the hereof the nut 6, and the lower portions ll ll I. ofauchdownwardlyextendedporflonsare bent outwardlysoastounderliethelowerfaceofthe nutasshowntothebestadvantageinl'ig. 3. At opposite sides oithewasher I the adjacent, inwardlyextended portions 0, downwardly extended portions ljr'and outwardly bent portions -ll oftheassociatedwasherportionsloand lb aredisposedadiacenttoeachothenandwhen thenutandwasherassemblyismountedonthe bolt these adjacently' disposed'portlons of said associated washer portions are located in the slotoftheboltasshowninlflgjwheretheysubstantiallyfllltlmoppositeendportions ofthe boltslotinatransversedirection.

Whenthewasherisbeingassembled with the nut, the outwardly bent portions ll ofthewasher portions la and lb extend downwardlyincontinu- 'ation of the portions ll of said washer portions andtheportionslF-ll ofbothwasherportions arepassedthrwghtheboreofthenutsoasto seattbeinnerfacesofthearcuateportionslof thewasherportionsonthefacel'ofthenut.- The portionsllofthewasherportlonsarethenbent outwardly,asshowninl'lg.3,sothattheyunderlietheoppositefaceofthenut. Itisobviousthat whenthewasherandnut havebeen assembled asdescribedthewasherporuonsmaynotbedisplacedtoanygrmtextentfromtheirpropereffective positions. This is sobecausethe opposed portions II and II oieach washer located in close proximity to opposed portions of thescrewthreadedwalloftheboreofthenut,prevent any great amount of movement transversely of the nut. Also very little movement ofthe 'washer portions away from each other is per- -views 01' the drawing. 7

'Ihe adjacently disposed, inwardly extuidcd,

portions! of theassociated washer portions la and lb which are located at'opposite sides of the washer are provided with inclined faces andthe inclined faces ofeach asociatedpairof portionslprovideaseatforawireorotherelement beingclamped by the connector. As shown inF'lg.3theseatsatoppmitesidesofthewasher arealined with each;other transversely oi'the slotoftheboltwhenthenutandwasherassembly aremountedonthe bolt.

Intheuseoftheimprovedconnectorillustrated v in the drawing the nut and washer asembly may beremovedfromthebolttopermitsaidbolttobe passed overawireL'whichmaybeconsidereda power line. Thenutandwasher asemblyisthen screwedonthescrewthrmded portions of the bolt with the arcuate portions 8 of thewasher portions la and lb embracing the outer curved facesof the legs of the bolt, and with the portions ll-ll of said washer portions disposed within theslotofthebolt. v'lhewireGwhichistobe electrically 'connectedto the wire L, a ground wire, for instance,isthenarrangedin place and thenutandwasherasscmblyisscrewedlongitudinallyofthe'boltuntilthewiresLandGare ilhtlyclampedbetweentheseatslandilofthe bolt and washer, during such movement the nut being rotated with respect to the washer which moves in a draight line. 4 a An extremely important feature of the invention is that when pressure is applied to the wires L and G to force them tightly together so that perfect electrical connection between said wires is provided, such pressure forces the curved surface 01' the wire G and the inclined seat faces I! of the washer portions 'la and lb into such close contact with each other that a camming action takes place which forces the washer portions outwardly from each other. This outward movement of the washer portions is transmitted to the legs I of the bolt by the washer portions located between said legs of the bolt with the result that said bolt l s are sprung outwardly slightly. As a result of the bolt legs being sprung outwardly as described the screwthreads formed on said bolt legs are forced into close cooperating relation with respect to the screwthreads within the bore of the nut whereby the desirable play-free cooperation between the screwthr'eads of the nut and bolt is obtained.

InFlg.isillustrated awasher II which is made from a single length of material. In accordance with this form of the invention the washer portions Ila and lib, which correspond to the washer portions lo and lb illustrated in Figs. 1 to 4, inclusive, are formed of the same length of material and are Joined together as indicated at It. In the use of this form of washer, the washer portions are spreadapart just as are the separate washer portions shown in Figs. 1 to 4, inclusive, to provide close cooperation between the screwthreads of the bolt legs and the nut, as the material of which the one-piece washer of Fig. 5 is formed is possessed of sufllcient spring to permit such movement.

While I have shown in the drawing two'forms of washers which are made from material of rectangular crow-section, it is to be understood that the washers may be made from material of round or other cram-sectional shapes without departing from the spirit of the invention? I claim: a v

1. An electrical connector comprising a. -bolt having spaced, exteriorly screwthreaded legs, a nut mounted on said screwthreaded bolt legs, and

- a washer arranged in assembled relation with respect to said nut and having portions which extend into the space between the legs of the bolt,

said washer including independent, substantially parallel portions movable outwardly away from each other when pressure is applied thereagainst and said outward movement of saidwasher portions being transmitted to the legs of the bolt by the washer portions between said bolt legs where- 'by the screwthreads of the bolt legs are forced into close cooperating relation with respect to the screwthreads of the nut.

2. An electrical connector comprising a bolt having spaced,1exteriorly screwthreaded legs, a'

nut mounted on said screwthreaded bolt legs, a washer arranged in assembled relation with respect to said nut and having portions which extend into the space between the legs of the bolt, and cam faces formed on portions of said washer, said washer including opposed portions movable outwardly away from each other when pressure is directed against said camfaces as a result of clamping pressure being applied toan element by said washer, and said outward'movement of said washer portions being transmitted to the legs of the bolt by the washer portions between the legs of the bolt whereby the screwthreads of the bolt legs are forced into close cooperating relation with respect to the screwthreads of the nut.

3. An electrical connector comprising a bolt having spaced, exteriorly screwthreaded legs, a nut mounted on said screwthreaded bolt legs, a washer arranged in assembled relation with respect to said nut and having portions which extend into the space between the legs of the bolt, and cam faces formed on portions of said washer which provide wire seats, said washer including opposed portions movable outwardly awayfrom each other when pressure is directed against said cam faces as a result of clamping pressure being applied to an element by said washer, and said outward movement of said washer portions being transmitted to the legs of the bolt by the washer portions between the legs of the bolt whereby the screwthreads of the bolt legs are forced into close cooperating relation with respect to the screwthreads of the nut.

4. An electrical connector comprising a bolt having spaced, exteriorly screwthreaded legs, a nut mounted on said screwthreaded bolt legs, a washer arranged in assembled relation with respect to said nut and having portions which extend into the space between the legs of the bolt, and inclined cam faces formed on portions of said washer, said washer including opposed portions movable outwardly away from each other when pressure is directed against said cam faces as a result of clamping pressure being applied to an element by said washer, and said outward movement of said washer portions being transmitted to the legs of the bolt by the washer portions between the legs of the bolt wherebythe screwthreads df the bolt legs are forced into close Cooperating relation with respect to the screwthreacls of the nut.

5. An electrical connector comprising a bolt having spaced, exteriorly screwthreaded legs, a nut mounted on said screwthreaded bolt legs, and a washer arranged in assembled relation with respect to said nut, said washerbeing formed of elongated material in strand form bent and 'tions outwardly.

shaped to provide portions which contact with .a face of the nut and portions which extend through the bore ofthe nut and underlie an opposite face of the nut, said washer portions which extend through the bore of the nut being located in the space between the legs of the bolt, independent, substantially parallel portions of said washer being movable outwardly away from each other when pressure is directed thereagainst as a result of clamping pressure applied to an elernent by said washer, and such outward movement of said washer portions being transmitted to the legs of said bolt by the washer portions between said legs of the bolt whereby the screwthreads of the bolt legs are forced into closecooperating relation with respect to the screwthreads of the nut.

6. An electrical connector comprising a bolt having spaced, exteriorly screwthreaded legs, a nut mounted on said screwthreaded bolt legs, a washer arranged in assembled relation with-respect to said nut, said washer being formed of elongated material in strand form bent and shaped to provide portions which contact with a face of the nut and portions which extend through the bore of the nut and underlie an opposite face of the nut, said washer portions which extend through the bore of the nut being located in the space between the legs of the bolt, opposed portions of said washer being movable outwardly away from each other when pressure is directed thereagainst as a result of clamping pressure applied to an, element by said washer, and such outward movement of said washer portions being transmitted to the legs of said bolt by the washer portions between said legs of the bolt whereby the screwthreads of the bolt legs are forced into close cooperating relation with respect to the screwthreads of the nut, and cam faces formed on portions of said washer, said cam faces providing wire seats and receiving thereagainst the pressure which moves said opposed washer por- 

